Python code formatter - Java Algorithm

Java examples for Algorithm:String

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Description

Python code formatter

Demo Code


import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.PrintWriter;
import java.nio.charset.Charset;
import java.nio.charset.StandardCharsets;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.util.Arrays;
import java.util.List;
import java.util.Vector;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class PyFormatter {
    public String m_fileString = "";
    public List<String> m_lines = new Vector<>();
    public int m_tabsNum;
    public String m_blockEndStr = "";

    public PyFormatter(String content, String blockEnd) {
        m_fileString = clearTab(content);
        m_tabsNum = 0;/* w w  w  .  j av  a 2s.  c o  m*/
        m_blockEndStr = blockEnd.toString();
    }

    public void format() {
        toLines(m_fileString);
        for (int i = 0; i < m_lines.size(); i++) {
            m_lines.set(i, getTabs(m_tabsNum) + m_lines.get(i));
            String thisLine = m_lines.get(i).trim();
            if (thisLine.length() == 0) {
                continue;
            }
            // not support reference after colon
            boolean hasColon = thisLine.charAt(thisLine.length() - 1) == ':';
            boolean hasWhile = thisLine.contains("while");
            boolean hasIf = thisLine.contains("if");
            boolean hasFor = thisLine.contains("for");
            boolean hasDef = thisLine.contains("def");
            if ((hasWhile || hasIf || hasFor || hasDef) && hasColon) {
                m_tabsNum += 1;
            }
            if (m_lines.get(i).contains(m_blockEndStr)) {
                String string = m_lines.get(i);
                Pattern pattern = Pattern.compile(m_blockEndStr); //case insensitive, use [g] for only lower
                Matcher matcher = pattern.matcher(string);
                int count = 0;
                while (matcher.find()) {
                    count++;
                }
                m_tabsNum -= count;
                if (m_lines.get(i).replaceAll("\\s", "").matches("^[;]+$")) {
                    m_lines.set(i, ";");
                } else {
                    m_lines.set(i,
                            m_lines.get(i).replaceAll(m_blockEndStr, ""));
                }

            }
        }
    }

    public String formatted() {
        String resultStr = "";
        for (String str : m_lines) {
            if (str.equals(";") == false) {
                resultStr += str;
                resultStr += "\n";
            }
        }
        return resultStr.substring(0, resultStr.length() - 1);
    }

    private String clearTab(String str) {
        return str.replaceAll("\t", "");

    }

    private void toLines(String content) {
        m_lines = new Vector<>(Arrays.asList(content.split("\n")));
    }

    private String getTabs(int num) {
        String result = "";
        for (int i = 0; i < num; i++) {
            result += "\t";
        }
        return result;
    }

    public static void main(String[] args) throws IOException {
        if (args.length != 2) {
            System.out
                    .println("Please type a source file name and a target file name");
            return;
        }
        String sourceFile = new String(args[0]);
        String targetFile = new String(args[1]);

        String text = "";
        try {
            text = readFile(sourceFile, StandardCharsets.UTF_8);
        } catch (IOException e2) {
            e2.printStackTrace();
        }
        PyFormatter formatter = new PyFormatter(text, ";");
        formatter.format();
        String result = formatter.formatted();

        PrintWriter fout = null;
        try {
            fout = new PrintWriter(targetFile);
            fout.print(result);
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } finally {
            fout.close();
        }

    }

    private static String readFile(String path, Charset encoding)
            throws IOException {
        byte[] encoded = Files.readAllBytes(Paths.get(path));
        return new String(encoded, encoding);
    }
}

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